749
FXUS62 KMHX 130848
AFDMHX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC
445 AM EDT TUE AUG 13 2013
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST THIS AFTERNOON AND
MOVE THROUGH THE AREA LATE TONIGHT AND WEDNESDAY. THE FRONT WILL
LINGER JUST OFFSHORE THURSDAY AND FRIDAY...THEN ALONG THE COAST
DURING THE WEEKEND...WITH AREAS OF LOW PRESSURE MOVING ALONG IT.
&&
.NEAR TERM /TODAY/...
AS OF 400 AM TUESDAY...BROKEN LINE OF TSTMS ASSCTD WITH WEAK SHRT WV
WILL MOVE ACROSS AREA THROUGH 7 AM...WITH HEAVY DOWNPOURS AND
FREQUENT LIGHTNING. MESO MODELS INDICATE THIS ACTIVITY MAINLY N AND
E OF AREA BY AROUND 8 AM...WITH LULL FOR REST OF MORNING. A FEW
OTHER SHOWERS/TSTMS CANNOT BE RULED OUT AND WILL CARRY 30 POP.
THREAT OF MORE WIDESPREAD SHOWERS AND TSTMS WILL DEVELOP DURING AFTN
WITH STRONGER SHRT WV APPROACHES IN GRADUALLY DEVELOPING LONG WV
TROFFING. INCREASING CAPE TO AROUND 2000 J/KG AND BULK SHEAR TO
25-30 KT SUPPORT STRONGER STORMS AND DAMAGING WIND THREAT...AND SPC
HAS EXPANDED SLIGHT RISK TO ENTIRE CWA...AND HAVE ADDED ENHANCED
WORDING WITH STORMS FOR THIS AFTN INTO EVENING. TORRENTIAL
DOWNPOURS/LOCALIZED FLOODING WILL ALSO BE LIKELY GIVEN CONTINUED
HIGH PRECIPITABLE WATER AND POTENTIAL FOR TRAINING OF CELLS.
SHARPENING PRE-FRONTAL THERMAL TROF AND SOME INSOLATION THIS MORNING
INTO EARLY AFTN SUPPORT MAX TEMPS INTO LOWER 90S AGAIN INLAND WITH
MID-UPR 80S BEACHES.
&&
.SHORT TERM /TONIGHT/...
AS OF 400 AM TUESDAY...BROKEN COVERAGE OF SHOWERS/TSTMS IN ADVANCE
OF COLD FRONT EXPECTED TO SPREAD NW TO SE OVER AREA DURING THE NIGHT
AND ADJUSTED TIMING OF LIKELY POPS ACCORDINGLY. SOME CAA BEHIND
FRONT MAY REACH NW SECTIONS LATE TONIGHT AND ALLOW TEMPS TO DROP TO
AROUND 70...WITH REST OF AREA IN LOW-MID 70S.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 3 AM TUE...NO MAJOR CHANGES TO THE LONG TERM FORECAST. THE
GFS AND ECMWF ARE IN GOOD AGREEMENT INTO THE FIRST HALF OF THE
WEEKEND. THE STATIONARY FRONT WILL LINGER JUST TO THE SOUTH
THROUGH SATURDAY. THE UPPER TROF OVER THE EASTERN U.S. WILL SLOWLY
LIFT OUT BY THE END OF THE WEEK. DIFFERENCES IN THE UPPER PATTERN
DEVELOP THIS WEEKEND. BOTH MODELS SHOW A STRONG SHORTWAVE DIVING
DOWN THE BACK SIDE OF THE UPPER TROF. THE ECMWF FORMS A CUTOFF LOW
EARLY NEXT WEEK TO THE WEST...WHILE THE GFS HAS A WEAKER UPPER
TROF AXIS TO THE WEST. AT THE SURFACE THE RESULT OF THIS IS TO
BRING THE STATIONARY FRONT A BIT FURTHER NORTH AND HAVE IT ALIGNED
NE-SW ALONG OR JUST INLAND FROM THE COAST. NOT MUCH CHANGE IN THE
RAIN CHANCES...RANGING FROM CHANCE TO LIKELY EACH DAY.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH 06Z WEDNESDAY/...
AS OF 130 AM TUESDAY...SCT SHOWERS/TSTMS WILL AFFECT TAF SITES
THROUGH 12Z WITH KPGV AND KISO MOST LIKELY TO SEE ACTIVITY IN VCTY.
AFTER INITIAL ACTIVITY...VFR CONDITIONS EXPECTED MOST OF MORNING
HOURS...THEN SCT SHOWERS/TSTMS EXPECTED AGAIN DURING AFTN AS COLD
FRONT APPROACHES FROM W-NW. LINE OF STORMS LIKELY TO IMPACT TAF
SITES AND HAVE ATTEMPTED TO TIME WITH TEMPO GROUP FROM NW TO SE
DURING 20Z-02Z PERIOD. MAIN ACTIVITY EXPECTED TO SHIFT TO NEAR COAST
BY 06Z BUT SCT SHOWERS MAY LINGER INLAND THROUGH LATE EVENING HOURS.
GUSTY SW WINDS EXPECTED AHEAD OF FRONT THIS AFTN AND EVENING.
LONG TERM /WED THROUGH SAT/
AS OF 3 AM TUE...BACKDOOR COLD FRONT WILL HAVE JUST MOVED SOUTH
OF THE FOUR AREA TERMINALS WEDNESDAY MORNING. NORTH WIND WEDNESDAY
WILL VEER SLIGHTLY TO NORTHEAST WEDNESDAY NIGHT AND CONTINUE
THROUGH SATURDAY. SPEEDS WILL BE LIGHT THROUGH THE PERIOD...NO
HIGHER THAN AROUND 10 KNOTS. SCATTERED TO NUMEROUS SHOWERS AND
STORMS ARE FORECAST EACH DAY WITH ACCOMPANYING LOWER CIGS/VSBYS.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 400 AM TUESDAY...APPROACHING COLD FRONT WILL RESULT IN
TIGHTENING PRES GRADIENT INTO THIS EVENING...WITH SW WINDS
INCREASING TO 15-20 KT SRN AND CENTRAL WATERS. WW3 AND SWAN AGREE
THAT PERIOD OF 6 FT SEAS WILL AFFECT OUTER PORTIONS OF CENTRAL
WATERS AND HAVE POSTED SCA THERE FOR THIS AFTN UNTIL LATE TONIGHT.
WINDS AND SEAS WILL SUBSIDE LATE TONIGHT AS FRONT PUSHES INTO AREA.
LONG TERM /WED THROUGH SAT/
AS OF 3 AM TUE...BACKDOOR COLD FRONT WILL BE MOVING THROUGH THE
SOUTHERN WATERS WEDNESDAY MORNING...BECOMING STATIONARY JUST TO
THE SOUTH DURING THE DAY AND LINGERING INTO THIS WEEKEND. NORTH
FLOW ON WEDNESDAY WILL VEER TO NORTHEAST WEDNESDAY NIGHT AND
CONTINUE INTO SATURDAY. PRESSURE GRADIENT WILL NOT BE VERY TIGHT
AND AM FORECASTING CONDITIONS TO REMAIN BELOW SMALL CRAFT
CRITERIA.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 6 AM
EDT WEDNESDAY FOR AMZ152-154.
&&
$$
SYNOPSIS...JBM
NEAR TERM...JBM
SHORT TERM...JBM
LONG TERM...HSA
AVIATION...JBM/HSA
MARINE...JBM/HSA